Ibm Aix

PCI RS/6000 Start up Process Overview Power On POST Locate OS Bootstrap Image Find AIX Boot Image Load AIX Boot Image RAMDISK created Configuration Manager Phase 1

INIT Normal IPL

AIX Startup on itanium- based System IBM POWER processor

ROS

SMS / bootlist

•ROS / SOFTROS •BLV

Intel Itanium – based processor

Hardware Initialization Low level configuration Load boot Image

AIX initialization

BIOS / EFL

Setup EFI Boot Manager

•EFI system partition boot.efi •volume partition BLV

alog User Applications

Boot Process

NIM

Install Process

Alog program /var/adm/ras/bootlog /var/adm/ras/Bosmenus.log Use alog command to view logs

/var/adm/ras/nosinst.data . .

To view the boot log: #alog –o –t boot

/var/adm/ras/erriog

System Resource Controller •Provides a single interface to control subsystems •Controls individual or groups of subsystems

Subsystem group

spooler

Subsystem

qdaemon

Subserver

qdaemon

writesrv

writesrv

ipd

Ipd

System Resource Controller Syntax List SRC Status # Lssrc –g spooler Subsystem

Group

PID

Status

Qdaemon

Spooler

8022

active

Writesrv

Spooler

9558

active

Lpd

Spooler

inoperative

Start a Subsystem # startsrc –s lpd 0513-059 The lpd Subsystem has been started. Subsystem PID is 12472. Refresh a Subsystem # refresh –s lpd 0513-095 The request for subsystem refresh was completed successfully Stop a Sybsystem # stopsrc –s lpd 0513 -044 The lpd Subsystem was requested to stop.

Device States Predefined Database Undefined

Supported Device rmdev -dl rmdev -dl

Mkdev Or cfgmgr

Customized Database rmdev -l Defined Available

Not Usable Ready for Use

Self-Configuring Devices 2. Answer -CD – ROM -04 – C0-00 – 3,0 1.Who are you

cfgmgr 4a) Load device driver 4b) Make /dev/cd0 entry ODM

Device Driver

3.cd0 defined

Cd0

Device Driver

Kernel /unix

Defined

22

04-c0-00-3,0

ODM

# ls –l /dev/cd0 Br—r—r– root

Cd0 Available 04-c0-00-3,0

5.Device available

System 22,

2

/dev/cd0

Location Code Format for SCSI Devices AB – CD – EF – G , H AB – CD

Identifies the bus and the adapter location Same as with non SCSI devices

EF

For a single SCSI bus -00 For a dual SCSI bus Internal bus - 00 External bus – 00

G,H

G – SCSI address ( SCSI ) of the device H = Logical unit number of the devices

Location Code Example for SCSI Device SCSI Devices (Disk, Tape, CD-ROM)

System Unit 04-01-00-4,0 SCSI Adapter

4

04-01-00-6,0

7 6 SCSI Bus

04-01 0

SCSI ID

Traditional UNIX Disk Storage Partition 1

Partition 2

Free space PROBLEMS: •Fixed partitions •Expanding size of the partition •Limitation on size of a file system and a file •Contguous data requirement •Time and effort required in planning ahead

Partition 3

Free space

Benefits of the LVM Logical volumes solve non – contiguous problems Logical volumes can span disks Dynamically increase logical volume size Logical volumes can be mirrored Hard disk easily added to a system Logical volumes can be relocated Volume group and logical volume statistics can be collected These task can be performed dynamically!

Physical Storage Volume Group A

Volume Group B

PV1

PV2

PV3

PV4

PV5

PP1

Physical Partitions 4MB is Default size 1016 max per PV

PP2 PP3 PP4 PP5 PP. PP.

Physical Volume /dev/hdiskn

Volume Groups rootvg

datavg

PV1 PV2 New PVs: •Add to existing VGs •Create new VG Why create new volume groups? •Separate user data from operating system files •Disaster recovery •Data portability •Data integrity and security

PV4

PV3

Volume Group Descriptor Area One disk VG

VGDA VGDA

Max size Normal VG-32 PVs Big Vg-128 PVs

Three disk or more VG

Two disk VG

VGDA VGDA

VGDA

VGDA

VGDA

VGDA

VGDA

Volume Group Limits Normal Volume Groups (mkvg) Number of disks:

Max.number of partitions/disk

1

32512

2

16257

4

8128

8

4046

16

2032

32

1016

Big Volume Groups (mkvg- B)

Mkvg -t

Number of disks:

Max.number of partitions/disk

1

130048

2

65024

4

32512

8

16256

16

8128

32

4064

64

2032

128

1016

Uses of Logical Volumes A logical volume may contains one of the following , and only one at a time: Journaled or Enhanced journaled file system ( for example : / dev hd4 Paging space ( dev/hd6 ) Journal log ( /dev/hd8 ) Boot Logical Volume ( /dev/hd5 ) Nothing ( raw device )

What Is File System ?      

A File System is Method of storing data Hierarchy of directories Four types supported : Journaled File system ( jfs2 ) Enchanced Journaled File System ( jfs2 ) CD – ROM File System ( cdrfs ) Network File System ( nfs ) Different file systems are connected together via directories to form the veiw of files users see

Why Have File System ? Can strategically place it on disk for improved performance Some tasks are performed more efficiently on a file system than on each directory within the file system, for example , back up, move, secure an entire file system Can limit disk usage of users by file system ( quotas ) Maintain integrity of the entire file system structure, for example ,if one file is corrupted ,the others are not affected Special security situations Organize data and programs into groups for ease of the file management and better performance

Standard File Systems in AIX hd4 (root)

home sbin lib

hd1

lpp

usr

bin

hd2

Bin lib lpp share sbin

dev tftpboot var mnt etc

hd9var

Spool adm tmp

tmp

hd3

Listing Logical Volume Information List all Logical Volumes by Volume Group: # lsvg –l rootvg LVNAME

Type

Lps

PPs

Pvs

Lv

STATE Mount Point

Hd6

paging

64

64

1

open/syncd

N/A

Hd5

boot

1

1

1

Closed/syncd

N/A

Hd8

jfslog

1

1

1

open/syncd

N/A

Hd4

jfs

2

2

1

open/syncd

/

Hd2

jfs

156

156

1

open/syncd

/Usr

Hd9var

jfs

1

1

1

open/syncd

/var

Hd3

jfs

3

3

1

open/syncd

/tmp

Hd1

jfs

1

1

1

open/syncd

/home

1v00

jfs2

2

2

1

open/syncd

/home/john

Volume Groups Volume Group

PV

PV

Physical Volume (PV)

Hard disk

Volume Group (VG)

Collection of related disks (PVs)

Hot Spare

1st copy of data1 LV

2nd copy of data1 LV

1st copy of data2 LV

Synchronization

Hot Spare

2nd copy of data2 LV

Mirroring Lv00

Hdisk() First Copy

PP1 PP2

Hdisk1 Second Copy

PP1 PP2

Hdisk2 Third Copy

PP1 PP2

LP1 LP2

Mirror Write Consistency Read Request Copy 1

Copy 2

Forced Synhronization Synchronize the Read Partitions

Copy 3

Logical Volume Policies Intra-physical volume allocation policy:

E

M

C

M

E

Ineer Edge Ineer Middle Center Outer Middle (Middle) Center Edge (Edge)

Inter-physical volume allocation policy: •Maximum number of PVs to use •Range of PVs to use

Migrating Physical Partitions

I/O Less Busy Disk

Busy Disk

Move Physical Partitions

# migratelp hd3/1 hdisk 1/109

Structure of a Journaled File System Superblock inodes

Indirect Blocks Data Blocks •

Superblock

1. File System size and identification 2. Free list, fragment size, nbpi •

Inodes

1. File size, ownership, permissions, times 2. Pointers to data blocks

• Blocks 1. Data blocks –contain data 2. Indirect blocks –contain pointers to data blocks.

Structure of an Inode

•Contents of an inode

Inode for file 1

Permission no.of links type of file user ID group ID file size address of blocks time modified time accessed time changed access control info. Reserved other

File System Fragmentation 4096 bytes

No Fragmentation File size = 2000 bytes

2000 bytes 2000 bytes

This free space cannot be used by another file Fragmentation Enabled File size = 2000 bytes Fragment size = 1024 bytes

2000 1024

bytes 1024

1024

1024

These free fragments can be used by other files

Variable Number of Inodes With the default nbpi=4096 on inode will be created for every 4096 bytes of file system. File System 4096 4096 4096 128 bytes

1 2

File System Using the value nbpi=1024 an inode will be created for every 1024 bytes of file system.

1 2 3 4

128 bytes

5 6 7 8

4096 4096

4096

Allocation Group Size Disk blocks

inodes

Groupings of related inodes and disk blocks.

16 MB 16 MB

16 MB agsize

16 MB Disk blocks

inodes

Groupings of related inodes and disk blocks.

64 MB 64 MB 64 MB

64 MB agsize

JFS vs.JFS2 File Systems JFS

JPS2

Maximum File Size Architectural /Tested

64 Gigabytes /64 Gigabytes

4 Petabytes / 1 Terabyte

Maximum File Size Architectural /Tested

1 Terabyte / 1 Terabyte

4 Petabytes / 1 Terabyte

Inode Size

128 Byters

512 Bytes

Number of inodes

Fixed. Set at creation

Dynamic

Fragments/ Block Size

512/4096

512/4096

Online defragmentation

Yes

Yes

Avaiable on itaum

No

Yes

Avaiable on POWER

Yes, default

Yes

Large File Enabled File Systems File = 132 MD (1024 * 4 KB blocks)+ (1024 * 128 KB blocks)= 132MB 4MB

+ 1 2

1025 1 Block 4 MB 1026

3

1027

4

.

.

= 132MB

32 Blocks 128 KB

1055

1023

1056

1024

File 132 MB

128MB

128 KB 1057 1058 1059 .

32 Blocks 128 KB

Journal Log Write data 1 Fsync() 1) Inode changes to log 3

2) COMMIT to log

2

3) Update inode 4) Sync log

inodes Data block

4

JFSLOG

No journaling of data blocks –only journals inode information (and indirect block information.)

Space Management File system expand upon notice, not automatically To keep from running in to problems : Monitor file system growth Determine cause Control growing files Manage file system space usage Control user disk usage Defragment file system

Control Growing Files /var/adm/wtmp /var/spool/*/* $HOME/smit.log $HOME/smit/script $HOME/websm.log $HOME/websm.script /etc/security/failedlogin /var/adm/sulog

Skulker

   

The skulker command cleans up file system by removing unwanted or obsolete files Candidate files include ( can use file aging as criteria ): Those in /temp directory A.out file Core files Ed.hup files Skuler is normally invokes daily by the cron command as part of the root’s crontab file Modify the skulker shell script to suit local needs for the removal of files

What is Paging Space? RAM – 256 MD

RAM Usage Operating System

Database

TCP/IP

8MB FREE

Current applications Total =248 MB RAM Usage Operating System 4KB

Database

TCP/IP

Application

4KB

Paging Space

Paging Space Placement •Only one paging space per disk •Use disks with the least activity •Paging spaces roughly the same size •Do not extend paging space to multiple PV’s •Use multiple disk controllers

hd6

paging00

Paging01

AIX Product Offerings AIX Expansion Pack Bonus Pack LPPs AIX Documentation AIX Toolbox for Linux

Packaging Definitions Collection of Packages Complete Product

LOO: bos

Package: bos.INed

Package: bos.adt

Collection of Filesets

Fileset:

Fileset:

Fileset:

Bos.INed

Bos.adt.lib

Bos.adt.prof

Smallest Unit Specific Function

Fileset Naming LPP

Package

Fileset

Suffix

Bos.terminfo.print.data Message Convention: LPP.msg[.lang].package.fileset

Software Updates 5

Version

.

1

Release

MIGRATION

.

0

.

Modification

0

Fix

Smit update_all

Software States Fileset 5.1.0.0 (New Version)

Applied: 4.3.3.0

Install

Fileset 4.3.3.0 (Old Version) Applied fileset 5.1.0.0

Committed 5.1.0.0

Install

Committed Fileset 5.1.0.0

Commit or Reject Fileset 4.3.3.0 (Old Version)

Why Backup? •Data is very important: Expensive to recreate Can it be recreated? •Disaster recovery: Hardware failure Damage due to installation/repair Accidental deletion •Transfer of data between systems Reorganizing file systems •Defragmentation to improve performance •System image for installation •Checkpoint (befor/after upgrade) •Long term archive

Types of Backup Three types of backup:

System Records image backup of the operating system rootvg Full Preserves all user data and configuration files Incremental Records changes since previous backups Must be used carefully Very quick

Backup Strategy System backup

Full backup

Incremental backup

Incremental backup

AIX Print Subsystem : Advantages       

Powerful and flexible printer drivers System management tools Limits fields and option validation Easy printer customization Single step print device and queue creation Support for dial-in administration Customizable spooling subsystem

System V Print Subsystem: Advantages Compattability of interface programs Avilabilty of interface programs Security Support for forms Standard PostScript filters Long term strategy

Concepts of Queues File 1

Queue1 File 1 File 2

File 2

:

File 3 Queue2

/dev/Ip0

File 3 File 4 File 4 /dev/Ip1

Printer Data Flow # qprt -Pps [ -c ] file Ip

Print Request Ipr

qpr t

Copy of file ( if requested )

enq Queue

Spool Directory

monitors qdaemon starts

Print Request

Backend ( piobe )

Virtual Printer Defination submits file to prienter

/ev/Ip0d

System Files Associated with Printing /etc/qconfig /var/spool/* /var/spool/lpd/qdir/* /var/spool/qdaemon/* /var/spool/ipd/stat/* /var/spool/lpd/pio/@local

queue configuration files spooling directories queue requests temporary enqueued files line printer status information Virtual printer directories

Queue Status State

Description

DEV_BUSY

Printer is busy servicing other print requests

DEV_WAIT

QUEUE IS WAITING FOR THE PRINTER

DOWN

QUEUE IS DOWN AND NO JOBS WILL BE SERVICED FROM THIS QUEUE UNTIL IS BROUGHT UP

OPR_WAIT

THE QUEUE IS WAITING FOR OPERATOR INTERVENTION

QUEUED

JOB IS QUEUED AND WAITING

READY

Everything is ready to receive a print request

RUNNING

Print file is printing

UNKNOWN

Problem with the queue – need to investiage further to determine cause